Your Friend Started a Savings Plan with 3 Pennies and Each

Short Answer

Your friend started a savings plan with 3 pennies and each day she saved three times the amount she saved the previous day.Later you started a savings plan with 9 pennies and each day you saved 9 times the amount you saved the previous day.On the day that your friend had been saving for 8 less than 4 times as many days as you,you saved the same amount as your friend.How many days have you been saving?